Static Stability Analysis Of Long-span Concrete Cable-Stayed Bridge

The fundamental theory of nonlinear finite element and stability theory are described in this thesis particularly.The nonlinear solutions are discussed.The evaluating index, unstable criteria are also studied.The paper introduces the way to analyze elastic and nonlinear stability of cable-stayed bridge by ANSYS and the finite element modeling of cable-stayed bridge.This thesis takes the Masangxi Bridge as an example and adopts the general finite element software ANSYS to analyze its elastic and nonlinear stabilities.In the analysis, the structural nonlinearity and ultimate bearing capacity of members for reinforced concrete cable-stayed bridge were considered.The linear elastic stability and nonlinear stability of longest double cantilever, single cantilever and service states of this concrete cable-stayed bridge were analyzed.and some problems on nonlinear stability of bridge were also discussed. The nonlinear analysis considers only geometric nonlinearity and both geometric and material nonlinearities.According to the solutions, its unitary stabilities were evaluated and the buckling types of the representative phases were pointed.The influence on stability of construction error and structural parameters in elastic stability and the influence on stability of the cable sag effect, the beam-column effect and the large displacement effect in nonlinear stability which considered the geometric nonlinearity only is researched.A detailed comparison study on global static stability which considered both geometric and material nonlinearities under some critical cases is presented, including the variable in stability loads and ultimate bearing capacity of members.